{"product_id":"allen-bradley-1746-ba-replacement-battery-3v-1000mah-li-mno2","title":"Allen Bradley 1746-BA PLC Replacement Battery 3V 1000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAllen Bradley 1746-BA \/ 1747-BA SLC 500 — 3V Li-MnO2 Replacement Battery (1769-BA)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3V, 1000mAh lithium manganese dioxide cell for Allen Bradley SLC 500 series PLC processor modules. It fits the 1746-BA, 1747-BAS, 1747-L20, 1747-L30, and over 120 additional compatible modules. The cell maintains SRAM program memory and real-time clock data when the controller loses mains power.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSLC 500 and ControlLogix module coverage:\u003c\/strong\u003e\n    These modules share a common 3V lithium cell footprint and SRAM retention circuit. The same voltage rail powers both the memory backup and the RTC, so one cell covers both functions across the platform.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell on an SLC 500 chassis under simulated power-loss cycles. The BMS held the SRAM retention voltage above the 2.5V cutoff threshold throughout, and the RTC continued tracking accurately after restoration of mains power.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eHot-swap procedure — mandatory for this controller:\u003c\/strong\u003e\n    Always replace this battery with the PLC powered on and in RUN mode. Removing the cell while the controller is de-energised will collapse the SRAM supply immediately, erasing the ladder logic program. If power was off during the swap, reload the program from your programming device before restarting the process.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSRAM retention voltage threshold on the SLC 500 processor\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe SLC 500 processor holds SRAM content down to approximately 2.5V on the backup cell. Below that threshold, the memory controller drops power and the program is lost — there is no graceful save or partial retention. A cell that reads 2.7V on a multimeter may still be above the cutoff, but internal impedance rise means it can no longer supply the brief current spikes the SRAM needs. Capacity fade, not open-circuit voltage, is usually what triggers memory loss before the battery alarm fires.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBattery alarm not clearing after a confirmed good cell installation\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe SLC 500 battery alarm does not reset automatically once a new cell is installed. The fault bit must be cleared manually in RSLogix 500 or RSLogix Classic via the controller properties dialog, or by cycling the fault reset through the programming software. A new cell shipped in storage condition may also read slightly below 3V on arrival — it rises to rated voltage within a few hours on the PLC float charge circuit. If the alarm persists after clearing the fault bit and allowing the cell to charge, check that the cell is fully seated and the connector is making clean contact.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43415982538842,"sku":"BWCS-PLC769SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43415982571610,"sku":"BWCS-PLC769SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43415982604378,"sku":"BWCS-PLC769SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-PLC769SL-1.webp?v=1779758956","url":"https:\/\/batteryweb.com\/products\/allen-bradley-1746-ba-replacement-battery-3v-1000mah-li-mno2","provider":"BatteryWeb","version":"1.0","type":"link"}